During a medical procedure that requires the patient to be anesthetized, the patient's breathing functions are temporarily disabled. Ventilation is supplied to the patient through an endotracheal tube. This tube is inserted into the trachea, and is typically closed against the wall of the trachea by an inflatable cuff. However, the insertion of the tube involves risks, such as, damage to the vocal cords and a prolonged intubation procedure in which the patients breathing is stopped but oxygen is not yet delivered to the patient as the tube has not yet been inserted. It is estimated that about one third of deaths occurring during a surgical procedure while under anesthesia for morbidly obese patients are associated with the intubation process.
Some of the difficulties the user encounters include: the restriction of view as the tube is inserted, variations in the anatomy of the patients, an uncomfortable and unnatural position for the anesthesiologist while holding the instrument and the necessity for rapid intubation.
With the advent of video laryngoscopes and cameras, instrumentation has been improved to the extent that it can enable viewing of the cords and larynx on a video screen thereby facilitating the intubation of the patient in a relatively quick and safe manner. For example, U.S. Pat. Nos. 6,890,298, 6,875,169 and 7,044,909 are variously directed toward video imaging systems. However, typically the view provided by the equipment has been limited requiring more time for the user to intubate the patient.
For example, video laryngoscopes have been used to help facilitate the intubation of a patient. Video laryngoscopes typically contain a light guiding system, usually in the form of fiber optic cables, in order to bring light to the surgical area. Video laryngoscopes also typically contain an image guiding system, for example in the form of a rigid rod lens system, arranged in the blade of the laryngoscope, or in the form of an ordered, flexible fiber optic bundle. In these configurations, the image guiding system is utilized to transmit reflected light from the area ahead of the blade to a camera, which may be attached to the laryngoscope. Alternatively, it is known to affix an imager, which may comprise, for example, a Charge Couple Device (CCD), or Complementary Metal Oxide Semiconductor (CMOS) to the distal end of the laryngoscope blade. In this case, the image data may be transmitted to the camera affixed to the laryngoscope via electrical wires (or wirelessly) as digital image data.
While this configuration for a video laryngoscope does provide a user very useful information in the form of image data, a major problem with current systems is the limited field of view. For example, when the user is intubating the patient, the imaging device, typically positioned on the underside and distal end of the laryngoscope blade, only provides a view of the, roughly, two-thirds of the configuration of the anatomy (depending on the patient it could be more or less) with the lower one-third not visible to the user. This is because the laryngoscope is only advanced into the throat of the patient far enough to lift the tongue (the upper anatomy part of the epiglottis and the vocal cords) and facilitate the introduction of the Endotracheal Tube (“ETT”, and which typically comprises a flexible plastic) into the trachea.
A malleable aluminum stylet is an accessory used with the ETT (typically inserted into the tube) to provide the tube with additional rigidity for the intubation process. The anatomy of patients often requires that the tip of the ETT to have a sharper bend and be partially more rigid so as to introduce it through the vocal cords, which are located toward an anterior (at the 12 o'clock) position. The stylet, which may comprise a malleable aluminum rod covered with a plastic material (disposable) is slid inside the ETT and is used to increase the bend of the tip of the ETT and form the proper angulation for the particular patient. After intubation, the stylet is removed and the ETT remains in place.
So, a major problem with current systems is two-fold, 1) if the stylet is not provided with the proper angulation or bend radius prior to insertion of the ETT, the user must remove the ETT and bend the stylet to match the patient's particular anatomy (which takes additional time and is highly undesirable); and 2) as the ETT (and stylet) is advanced through the vocal cords, the view in front of the ETT blocked by the stylet and ETT.
While current systems do provide a view from the bottom of the laryngoscope blade, this view is limited to the upper portion of the patient's anatomy.